Common applications of silencer assemblies include gas turbine's intakes and exhausts, system bypasses and system stacks, and fresh air intakes to fans and fan discharges. For example, in power plants the energy is generated by a plurality of combustion turbines that release hot gas at very high noise levels. In many such systems, the hot gas (air) passes through a silencing system. Conventional silencing systems typically utilize a baffle configuration including parallel and spaced baffles, vertically positioned within the ducts or stacks. The baffles generally consist of smooth, perforated metal facings over absorptive elements arranged parallel to the flow passages. Specifically, the active length of the baffle face runs directionally with the gas flow. The baffles are used to split the gas flow into smaller chambers, often called air passages.
The baffles can be flat or concentric rings. The dimensions of the air passages (in the direction of the flow), coupled with the baffle thickness, baffle material, baffle active length, and duct casing configuration are the primary factors that contribute to the system pressure loss through the system and the acoustical performance, namely silencing. These conventional systems generally require flow distribution grids and/or turning vanes to ensure even distribution of the gasses through the air passages for reducing the pressure losses, enhancing the acoustical performance and providing the even distribution of the gas flow to the heat recovery steam generator.
In an effort to increase performance and the benefits of such silencing systems, it is desirous to eliminate the numerous flow distribution devices, to decrease the pressure loss through the system, to improve the acoustical silencing effect of the system, and to simplify the field installation process.